| 内容提要: |
The effect of catalytic hydrogenation liquefaction of sewage sludge over Ni-Mo catalysts in ethanol-water co-solvent with addition of aluminum was studied in this research. Al and catalytic could promote hydrogen produced during SS liquefaction in ethanol-water co-solvent and had a positive effect on the bio-oil yields. The yield of bio-oil increased gradually with increasing the amount of Al in solvent and the highest yields was 52.83% with 30% Al and 10% Ni-MoS in ethanol-water co-solvent. The main components of the bio-oils were phenols, esters, acids, hydrocarbons heterocycle compounds and N-compounds. Ni-MoS/Al2O3 and Ni-Mo/Al2O3 could effectively promote the formation of esters and decreased the heterocycle and N-compounds contents. Oxygen was effectively removed by catalytic hydrogenation. The atomic ratios of H/C and O/C significantly decreased by catalytic hydrogenation, and were lower than those of SS that could be attributed to the dehydration, dehydrogenation, decarboxylation, and esterification reactions.
Soybean isolate protein powder and starch powder were chosen as model compounds which were broke down to amino acids (glycine, glutamic acid, alanine, arginine, valine), sugars (glucose, reducing sugar, D-fructose), glycerol and fatty acids, respectively via hydrolysis reaction. Amines and fatty acids were produced due to amino acid deamination and decarboxylation reactions. Fatty acids or low carbon acid underwent decarboxylation or esterification reactions to form hydrocarbons (1-Hexadecene, 1-Eicosene, etc.) or aliphatic esters (Diethyl succinate, Ethyl laurate, Ethyl myristate, and Ethyl palmitate, etc.), respectively. Fatty acids or low carbon acid also could undergo cyclization reaction to form benzene compounds (benzofuran, 2,4-dimethy-quinolin and 4-Propylpyridine, etc.) or react with amine through acylation reaction to form amide (N-(1-Oxo-indan-5yl)-acetamide and stearamide). Reducing sugar or sugar underwent degradation to form cyclic oxygenates or decomposition reaction to form furfural derivatives or low carbon acids. Amino acids also could react with monosaccharides through Maillard reaction to form N-heterocyclic compounds such as 1-Methyl-2-pyrrolidinone, 2,3.5,6-pyridinetetramine, 2-piperidone and 3-methylindole, etc. CO2, CO and NH3 produced from decarboxylation and deamination reactions, thus increased the gas yield. Hydrocarbons, esters, amides, acids, benzene compounds, and N-heterocyclic compounds were regarded as bio-oils. |